<?php
namespace Matrix\Operators;
use Matrix\Matrix;
use Matrix\Exception;
class Subtraction extends Operator
{
/**
* Execute the subtraction
*
* @param mixed $value The matrix or numeric value to subtract from the current base value
* @throws Exception If the provided argument is not appropriate for the operation
* @return $this The operation object, allowing multiple subtractions to be chained
**/
< public function execute($value)
> public function execute($value): Operator
{
if (is_array($value)) {
$value = new Matrix($value);
}
if (is_object($value) && ($value instanceof Matrix)) {
return $this->subtractMatrix($value);
} elseif (is_numeric($value)) {
return $this->subtractScalar($value);
}
throw new Exception('Invalid argument for subtraction');
}
/**
* Execute the subtraction for a scalar
*
* @param mixed $value The numeric value to subtracted from the current base value
* @return $this The operation object, allowing multiple additions to be chained
**/
< protected function subtractScalar($value)
> protected function subtractScalar($value): Operator
{
for ($row = 0; $row < $this->rows; ++$row) {
for ($column = 0; $column < $this->columns; ++$column) {
$this->matrix[$row][$column] -= $value;
}
}
return $this;
}
/**
* Execute the subtraction for a matrix
*
* @param Matrix $value The numeric value to subtract from the current base value
* @return $this The operation object, allowing multiple subtractions to be chained
* @throws Exception If the provided argument is not appropriate for the operation
**/
< protected function subtractMatrix(Matrix $value)
> protected function subtractMatrix(Matrix $value): Operator
{
$this->validateMatchingDimensions($value);
for ($row = 0; $row < $this->rows; ++$row) {
for ($column = 0; $column < $this->columns; ++$column) {
$this->matrix[$row][$column] -= $value->getValue($row + 1, $column + 1);
}
}
return $this;
}
}